Codex Knowledge Base
Migrating from GitHub Copilot to Codex CLI
Before we begin: there is a naming trap to navigate. In February 2026, GitHub launched GitHub Copilot CLI.
Migrating from Cursor to Codex CLI
Cursor's June 2025 pricing overhaul — replacing predictable 500-request plans with variable credit pools — sent a visible slice of its user base searching.
GitHub Agentic Workflows: Intent-Driven Repository Automation with Codex
GitHub shipped GitHub Agentic Workflows in technical preview on February 13, 2026.
Evaluating Codex Agents: Evals, Long-Horizon Benchmarks, and the 4-File Pattern
How to evaluate whether your Codex agent actually did the right thing — from quick skill evals to 25-hour autonomous runs.
Debugging Codex Agent Failures: A Systematic Troubleshooting Guide
Codex CLI agent failures cluster into a small number of recognisable patterns. Most failures are not random — they have consistent causes and systematic.
Cross-Model Adversarial Review: Using Multiple AI Models to Catch Agent Blind Spots
The moment your coding agent reviews its own output, you have a problem. Not because the agent is dishonest.
The Codex TypeScript SDK: Embedding Agents in Your Own Tooling
The Codex CLI is powerful in interactive mode, but its real leverage comes when you embed it programmatically. The Codex TypeScript SDK (@openai/codex-sdk).
GPT-5.3-Codex-Spark: The Cerebras-Powered Ultra-Fast Coding Model
On 14 January 2026, OpenAI announced a multi-year partnership with Cerebras Systems. Four weeks later, on 12 February 2026, the first concrete output.
The codex-rs Architecture: How OpenAI Rewrote Codex CLI in Rust
When OpenAI open-sourced Codex CLI in April 2025, the codebase was TypeScript on Node.js — a deliberate choice for velocity.
Codex Model Lineage: The Context Compaction Breakthrough That Made Long-Horizon Agents Possible
If you've been using Codex CLI for agentic work, you've probably hit the wall: a long-running session starts hallucinating earlier decisions.